The invention relates to halichondrins and compounds related thereto, such as synthetic intermediates of halichondrins and derivatives of such intermediates.
Halichondrins are a class of polyether macrolides isolated originally from the marine sponge Halichondria okadai Kadota. Examples of halichondrins include halichondrin B, homohalichondrin B and homohalichondrin B, the structures of which have all been elucidated. Halichondrins exhibit an extraordinary in vitro and in vivo antitumor activity. However, the very limited supply of halichondrins from natural sources has prevented the full evaluation of their potential clinical applications.